Abstract：One handred fifty-four bacteria were isolated from tobacco leaves on the medium with nicotine as unique carbon source. A high nicotine-degrading bacterium (L1) was obtained after screening. Based on morphology, physiological and chemical tests, 16S rDNA sequence and phylogenetic analysis, L1 was identified as Bacillus simplex. The concentration of nicotine for the optimal growth of L1 was 1.0g/L. The nicotine was degraded up to 75% by strain L1 under the optimized incubation conditions for 36 h monitored by high-performance liquid chromatography. There was no pigment observed at degrading process. This study demonstrates that Bacillus simplex L1 had strong ability to degrade nicotine, and the degrading mechanism may be different from Arthrobacter sp.
